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Bucking = too much air?

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Old 12-29-2008, 08:36 PM
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Default Bucking = too much air?

Ok, EFI Alchemy did an amazing job on tuning my ASA Cam, but I am bored and I am trying to get my conveter locked a little lower in 4th. I can lockup at 60 without any issue, but 50 would be great. If I set the cruise @ 50, the converter will lock (Dont know why) and she bucks if i go down a hill locked up, but the bucking ceases once she comes under load again. I have no throttle cracker enabled. Could this be spark, or airflow (or both)?
Old 12-29-2008, 08:52 PM
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Bucking may be DFCO cycling in and out, catch a log of it
and look at whether the bucking events are showing 0
degrees advance and zero injector pulse width. If so then
DFCO is what's doing it. A lot of cams put you on the wrong
side of the fuel-cut criteria (MAP especially).
Old 12-29-2008, 09:10 PM
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Thanks Jimmy, stop by ecklers sometime and say hi if you are ever in Titsville
Old 12-29-2008, 09:41 PM
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For my particular setup, I had to add a couple of degrees of timing and get the fueling just right. It locks up at 50 mph for the 4th gear. Each setup is different, so you may have to experiment with the lockup in 1-2 mph increments. I would also make sure the TCC release speeds are not conflicting with the apply speeds. The TCC should release on decel and going up a hill or grade to prevent lugging.
Old 12-29-2008, 10:19 PM
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Hi Drew,
Longtime no see. Are you sure are locked? I mean your scan tool might show a commanded lock but, you maybe losing pressure due to one of many things...the most recent we have seen was an input shaft housing bleeding off pressure.

Don't be a stranger, drop us a line.

Doc
Old 12-30-2008, 06:04 PM
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Originally Posted by Doc
Hi Drew,
Longtime no see. Are you sure are locked? I mean your scan tool might show a commanded lock but, you maybe losing pressure due to one of many things...the most recent we have seen was an input shaft housing bleeding off pressure.

Don't be a stranger, drop us a line.

Doc
Well since I have such a loose TC, I can feel when I lock up, it feels like 5th gear. I will disable DFCO and see how low she will go, lol. Thanks for all the help guys.
Old 12-30-2008, 07:34 PM
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cldnt a fuel pump going out also cause bucking?
Old 12-30-2008, 10:41 PM
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fuel pumps in these cars just die, at least thats my experience




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